Overthrow mechanism



March 1935- w. J. PEARSON ET AL 2,035,715

OVERTHROW MECHAN I SM Filed April 9, 1932 2 Sheets-Sheet l Fig. 1.

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OVERTHROW MEGHAN I SM Filed April 9, 1932 2 Sheets-Sheet 2 ii L .175 660I 7 4 5665 Z llh "l NW 'lfl 44 HLLO 4. William Jlkansaon T homais 1.171mun Patented Mar. 31, 1936 UNITED STATES PATENT OFFICE OVERTHROWMECHANISM geles, Calif.

Application April 9, 1932, Serial No. 604,294

7 Claims.

One of the objects of our invention is to provide an overthrow mechanismso constructed as to prevent the spinning of the register wheels at thetime when the operating means has reached the limit of its travel.

A further object is to provide means for locking said registering wheelswhen said operating means is moving from normal position and means forreleasing said locking mechanism while the operating means is returningto normal position.

Another object of our invention is to provide a convenient means for thenormal resetting of the register wheels in a meter unit so that they maybe placed in any decided position without the necessity of previouslyreleasing the register locking mechanism.

In the drawings:

Figure 1 is a sectional view through the meter unit.

Figure 2 is a sectional view taken on line 2-2 of Figure 1 with one ofthe register wheels shown in section, the others being in elevation.

Figure 3 is an enlarged elevation of one of the wheels and taken on line3-3 of Figure 2.

Figure 4 is an enlarged elevation of one of the register wheels andtaken on line 4-4 of Figure 2.

Figure 5 is an enlarged sectional view of a register wheel showing therelation of a spring ratchet dog to the internal and external ratchetnotches. This view also makes clear the assembly of the other parts ofthe register wheel.

Figure 6 is a fragmentary perspective View showing the relation of thevarious parts of the overthrow mechanism.

The overthrow preventing mechanism disclosed in this invention isincluded in the meter unit 65. Also included in the meter unit 65 are adescending register 11, and an ascending register 18, which registersare composed of a series of similar indicia wheels 364. For the purposesof this application we will refer to only one of each series. Theregister wheels are operated by the movement of the sector 441. Thepoint 446 of the sector 44'! engages with any suitable positioning means(not shown in this drawing) the position of which is predetermined bymeans of a controlling apparatus, thus limiting the movement of thesector 441. When the shaft 46| and the cam B, is rotated, the sector441, supported by the cam roller 445 is permitted to rotate, around theshaft 435i, under the influence of the spring 450 'until point 446engages with the aforesaid positioning means. This movement rotates thepinions 313 in a clockwise direction.

The overthrow mechanism consists of a multiple number of latches I, allof which are similar in construction and operation, the latch stop pin1, the connecting fork m, the spring IS, the operating lever l3, and thesprings 1. As shown in Figs. 1 and 6, the fork I9 is located on the neara side of the latch and the stop pin l" is provided to insure thepositive withdrawal of the latch 1, While at the same time permittingthe spring I6 to stretch when the latch is engaged. The fork I0 isprovided with a slot it adapted to engage the stud l3 on the operatinglever l3. The latch engages with the ratchet wheels i8 and I9, which areriveted to the webs 353 of the indicia drums 364 as shown in Figures 4and 5. Any counter-clockwise motion of these wheels is prohibited whilethe latch is so engaged, by means of the fingers 20 and 2|. Upon theshaft 46| being rotated in a counterclockwise direction, the cam surface24 which is rigidly fixed to the cam B is revolved until it disengagesfrom the point 25 of the lever l3, permitting said lever to movecounterclockwise under the influence of the spring H.

The disengagement, so eifected, is timed to occur after the completionof the downward movement of the point 446, and before the beginning ofthe upward movement of the said point. Upon the furthercounter-clockwise rotation of shaft 46| the cam B engages with the camroller 445 and restores the sector 44? to its normal position. Thisclock-wise movement of the sector 441 is transmitted to a counterclockwise movement in pinions 313 and through them to the indicia drums364 by means of the ratchet dogs 315 as will be further explained. Theleading edge 26 of the cam 24 is so disposed that it will engage thepoint 25 of the lever i3 at the moment when the roller 44% and thesector 44'! have attained their maximum clock-wise movement. When thelever I3 is forced back by the cam surface 24, the motion is transmittedthrough the fork ID, the spring l6, and the latch l, to the fingers 20and 2|, which engage with the ratchet wheels l8 and I9, said ratchetwheels being an 45 integral part of the indicia drums 364 as will beshown. By this means the indicia drums are brought to a definite stop atthe moment when the sector 44'! ceases to impart motion, and any furthermovement of the wheels 365; due to momentum or other causes is renderedimpossible.

The spring I6 is included in the power transmission means as a safeguard against undue pressure on the fingers 23 and 2| and also toprovide a means of manually releasing the latch 1 without revolving theshaft 46!. This operation is performed as fo1lowsWhen the door 294 inthe cover plate 296 is opened the cam surface 29 is rotated around theshaft 30 so as to engage with the cam surface 3! of the latch 1 and torotate the said latch in a clock-wise direction around the shaft 39!,thus disengaging the latch 1 from the ratchet wheels I8 and i9, and sofrom the indicia drums 364. This feature is included as a convenience inthe manual resetting of the wheels 364 in the descending register 11.

r The construction of the register wheel 364 is made plain by referringto Figures 3, 4 and 5, and the relation of the cam surface 24, theoperating lever [3, the fork l6, and the latch 1 to the ratchet wheelsl8 and I9, is illustrated in Figure 2, which is a partial sectionalelevation through line 2-2 of Figure 1. The relation of the sector 441and cam roller 445 to the cam B is also shown in this figure.

The register wheels 364 include an inner sleeve 356 having a spring disc351 provided on the inner end thereof, this disc having two spring dogs358 which are deformed so as to be continually urged in the direction inwhich one of these is shown in Figure 5. On the opposite end of thesleeve 356 is rigidly mounted a large diameter transfer gear 366 whichis shown in Figure 2.

Rotatably mounted on the sleeve 356 is a sleeve 36!, which has a flangeat its inner end, upon which is secured the web 363 of an indicia drum364. The indicia drum 364 is adapted to carry digits from one to nineand zero, serially arranged. Also secured to the sleeve 36! is acarry-over disc 366, which in the present embodiment is formed by a pairof discs, the outermost of which is provided with ratchet notches 361,which are adapted to receive the dogs 358 as shown in Figure 5. Thereare ten of the ratchet notches 361 which are uniformly spacedcircumferentially about the axis of the disc 366, as shown in Figure 4.The disc 366 has a recess 368 formed therein and a pair of teeth 366 areprovided to extend outwardly from the disc alongside of this recess asshown in Figure 4.

Formed in the inner face of the web 363 of the indicia drum 364 are tenratchet notches 310 which are similarly arranged to the ratchet notches361.

Rotatably mounted on the sleeve 36! is a third sleeve 312 having a gear313 at its outer end and carrying a spring dog plate 314 on its innerend, there being a pair of oppositely disposed spring dogs 315 formedfrom this plate so as to be continually urged into engaging with theratchet notches 316 as shown in Figure 5.

A series of register wheels 364, are placed close together on the shaft355to form the descending register 11 so that the carry-over gear 366 ofeach of these wheels is disposed adjacent to the carryover disc 366 ofthe adjacent register wheel. The teeth 39!! of the carry-over gears 402are disposed in the same radius, and are of the same pitch as the teeth369 on the carry-over disc 366 and the teeth of the carry-over gears366.

The ratchet wheels !8 and !9 are rigidly fixed as by rivets 362 betweenthe webs 363 of the indicia drums 364 and the discs 366 as shown inFigure 5. The teeth of the ratchet Wheels are so disposed as to engagewith the fingers 26 and 2! of the latch 1 at the moment when the fingersare depressed by the influence of the cam surface 24 on the point 25 ofthe operating arm I3.

Included in the assembly of the wheels 364 are two spacers 32 which willpreclude any possibility of the fingers 26 and 2! binding on either thedrum 364 or the disc 366. r

, While the construction shown and above described is entirelysatisfactory for the purpose primarily set forth, the ideas are capableof various embodiments, with suitable. modifications and changes, allcoming within the scope of the claims which follow.

A more detailed description of the operation is as follows: The rotationof the cam B by means of the shaft 46!, to which it is rigidly fixed,permits the counterclockwise movement of the sector 441 when the surfaceB of the cam B is removed from the path of the roller 445. This movementof the sector 441 is imparted to each of two pinions 313, whichtogether, with their respective spring ratchet dogs 315, are impelled ina clockwise direction.

The pinions 313 are mounted within the register Wheel assembly 11, andare so constructed as to turn in this direction without influencing theposition of the indicia drum 364, the Geneva tooth 369 or the carry-overpinion 390. The indicia drum is held against clockwise movement by theexternal spring ratchet dog 358, to which it is rigidly aflixed, and theaforesaid pinion 396.

The movement of the sector 441, if unchecked would continue until theroller 445 came to rest on the low point of the cam B and this movementis designed to be equal to exactly nine teeth on the sector 441 and thepinion 313 which in turn will equal nine ratchet teeth 316 in theindicia drum 364. However, the counterclockwise movement of the sector441 may be arrested at any one of nine equal spaces, each correspondingto one ratchet tooth 316, by the introduction of any suitable stop suchas a step of a step-cam under the point 446 of the sector 441.

At this point in the rotation of the cam shaft 46!, the point 25 of thearm !3 disengages from the surface 24 of the cam 26 and the arm moves ina counterclockwise direction under tension of the spring 11. This motionis transmitted through the stud !3, the slot !0' of the fork l0, and thestud 1 to the latch 1, which moves in a clockwise direction a distancesufficient to disengage the hooks 26 and 2! from the teeth of theratchet discs !8 and !9 which discs are rigidly aifixed to theirrespective indicia drums 364.

Upon further movement of the cam shaft 46! the leading edge of the cam Bengages the roller 445 of the sector 441 and impells said sector in aclockwise direction. This movement is transmitted to the pinions 313 ineach of the two register wheels, and so tothe ratchet dogs 315. Thecounterclockwise movement of the said ratchet 'dogs 315 is imparted tothe indicia drum 364 by means of the ratchet teeth 310 with which thedogs engage.

It is obvious then, that the amount of clockwise -movement of the sector44'! is determined by the counterclockwise movement previously impartedby the spring 450 and limited by the position of a stop placed under thepoint 446, so that when the roller 445 of the sector 441 is fullyrestored to the high point of the cam B, the pinions 313 will haveturned a number of teeth corresponding to the position of said stopunder point 446.

Furthermore, this counterclockwise movement of the pinions 313 will turnthe indicia drum 364 a corresponding distance and a new figure willappear in the window 294. However, the momentum imparted to the indiciadrum 364 might cause said drum to continue its motion after its drivingratchet dog 315 had come to rest, so at the precise moment that the.roller arrives at the highest point on the cam B, the leading edge ofthe cam 26 engages the point 25 of the arm l3.

The clockwise movement so imparted to the arm I3 is transmitted throughthe stud l3, the slot of the fork l0, and the spring I 6 to the latch'l. The hooks 20 and 21 of the latch 1 engage simultaneously with eachof the two register wheels and the said engagement is so timed as tooccur when the driving dogs 315 reach the limit of theircounter-clockwise motion. This completes one cycle of the mechanism.

I claim:

1. In an overthrow preventing mechanism, latching means, an operatinglever, said means comprising a latch, and a fork, said fork connectingsaid latch and said lever said latch and said fork being constrained toact simultaneously by a spring.

2. In combination with a meter unit, two register wheels and means forsimultaneously looking sai-d register wheels, said means comprising alatch common to said register wheels and operating means for said latch,said operating means consisting of a positively driven cam and a leverconnecting said latch and said operating means.

3. In combination with a meter unit, two register wheels and means forsimultaneously looking said register wheels, said means comprising alatch common to said register wheels and operating means for said latch,timing means so arranged as to prevent movement of said register wheelsbeyond the points to which they are positively driven.

4. In combination with a meter unit, a gear sector plate in said unit,two register wheels and means for simultaneously locking said registerwheels, said means comprising a latch common to said register wheels andoperating means for said latch, timing means comprising a cam and alatch operating arm, said arm arranged to operate in conjunction with aregister operating sector plate.

5. In combination with a meter unit, two register wheels, means forsimultaneously locking said register wheels, gear sector plates in saidmeter for actuating said register wheels, means for causing said sectorplates to move from normal position and means for causing said lockingmeans to remain engaged with said register wheels during said movementof said sector plates.

6. In combination with a meter unit, two register wheels, means forsimultaneously locking said register Wheels, gear sector plates in saidmeter for actuating said register wheels, means for causing said sectorplates to move from normal position and means for causing said lockingmeans to remain engaged with said register wheels during said movementof said sector plates, and means for releasing said locking means whilesaid gear sector plates are being restored to their normal position.

'7. In an overthrow preventing mechanism, latching means comprising amechanically operated device, said device comprising a latch, aconnecting fork, a spring controlling said connecting fork, an operatinglever and a cam, said latch and said operating lever connected togetherby said connecting fork said latch being constrained by said connectingmeans to engage simultaneously with two register wheels.

WILLIAM J. PEARSON. THOMAS I. BROWN.

